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2.
BMC Infect Dis ; 24(1): 885, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39210315

RESUMEN

BACKGROUND: Long-term sequelae of SARS-CoV-2 infection, namely long COVID syndrome, affect about 10% of severe COVID-19 survivors. This condition includes several physical symptoms and objective measures of organ dysfunction resulting from a complex interaction between individual predisposing factors and the acute manifestation of disease. We aimed at describing the complexity of the relationship between long COVID symptoms and their predictors in a population of survivors of hospitalization for severe COVID-19-related pneumonia using a Graphical Chain Model (GCM). METHODS: 96 patients with severe COVID-19 hospitalized in a non-intensive ward at the "Santa Maria" University Hospital, Terni, Italy, were followed up at 3-6 months. Data regarding present and previous clinical status, drug treatment, findings recorded during the in-hospital phase, presence of symptoms and signs of organ damage at follow-up were collected. Static and dynamic cardiac and respiratory parameters were evaluated by resting pulmonary function test, echocardiography, high-resolution chest tomography (HRCT) and cardiopulmonary exercise testing (CPET). RESULTS: Twelve clinically most relevant factors were identified and partitioned into four ordered blocks in the GCM: block 1 - gender, smoking, age and body mass index (BMI); block 2 - admission to the intensive care unit (ICU) and length of follow-up in days; block 3 - peak oxygen consumption (VO2), forced expiratory volume at first second (FEV1), D-dimer levels, depression score and presence of fatigue; block 4 - HRCT pathological findings. Higher BMI and smoking had a significant impact on the probability of a patient's admission to ICU. VO2 showed dependency on length of follow-up. FEV1 was related to the self-assessed indicator of fatigue, and, in turn, fatigue was significantly associated with the depression score. Notably, neither fatigue nor depression depended on variables in block 2, including length of follow-up. CONCLUSIONS: The biological plausibility of the relationships between variables demonstrated by the GCM validates the efficacy of this approach as a valuable statistical tool for elucidating structural features, such as conditional dependencies and associations. This promising method holds potential for exploring the long-term health repercussions of COVID-19 by identifying predictive factors and establishing suitable therapeutic strategies.


Asunto(s)
COVID-19 , Síndrome Post Agudo de COVID-19 , SARS-CoV-2 , Humanos , COVID-19/complicaciones , COVID-19/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Italia/epidemiología , Hospitalización , Sobrevivientes , Factores de Riesgo
3.
Am J Hypertens ; 37(10): 777-783, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39016523

RESUMEN

BACKGROUND: Myostatin is a protein compound, structurally related to the transforming growth factor-beta protein, which plays a pivotal role in regulating muscle growth and extracellular matrix production. It exerts both profibrotic and antihypertrophic effects on vascular smooth muscle cells. Aim of the study was to explore the potential association between serum myostatin levels (sMSTN) and carotid-femoral pulse wave velocity (cf-PWV), carotid-radial pulse wave velocity (cr-PWV), and their ratio (PWVr), in a cohort of healthy adolescents. METHODS: A cohort of 128 healthy subjects (mean age 17 ±â€…2 years, 59% male) was randomly selected from participants to the MACISTE (Metabolic And Cardiovascular Investigation at School, TErni) study. sMSTN was assessed utilizing an enzyme-linked immunosorbent assay. PWVs were measured in the supine position using high-fidelity applanation tonometry. RESULTS: The mean cf-PWV was 5.1 ±â€…0.9 m/s, cr-PWV was 6.9 ±â€…0.9 m/s, and PWVr was 0.75 ±â€…0.12. PWVr exhibited a linear increase across increasing quartiles of sMSTN (0.71 ±â€…0.1, 0.74 ±â€…0.1, 0.7 ±â€…0.1, 0.77 ±â€…0.1, P for trend = 0.03), whereas the association between sMSTN and each single component of PWVr (cf-PWV, cr-PWV) did not attain statistical significance. Quartiles of sMSTN displayed a positive trend with serum HDL-cholesterol (P = 0.01) and a negative one with LDL-cholesterol (P = 0.01). In a multivariate linear model, the association between PWVr and sMSTN was independent of SBP values, age, sex, heart rate, BMI, HDL-cholesterol, and HOMA Index. CONCLUSIONS: In healthy adolescents, sMSTN showed independent associations with PWVr, a measure of central-to-peripheral arterial stiffness gradient. sMSTN may exert differential effects on the structural and functional properties of the arterial wall.


Asunto(s)
Miostatina , Rigidez Vascular , Humanos , Masculino , Miostatina/sangre , Adolescente , Femenino , Velocidad de la Onda del Pulso Carotídeo-Femoral , Análisis de la Onda del Pulso , Biomarcadores/sangre , Estudios Transversales , Voluntarios Sanos , Ensayo de Inmunoadsorción Enzimática
4.
Mol Metab ; 68: 101674, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36657563

RESUMEN

OBJECTIVE: Thioalbamide is a ribosomally synthesized and post-translationally modified peptide (RiPP) belonging to the family of thioamitides, a rare class of microbial specialized metabolites with unusual post-translational modifications and promising biological activities. Recent studies have demonstrated the ability of thioalbamide to exert highly selective cytotoxic effects on tumor cells by affecting their energy metabolism, thus causing abnormal ROS production and triggering apoptosis. This study is aimed to investigate the molecular mechanisms underlying the antitumor activity of thioalbamide in order to identify its exact molecular target. METHODS: Wild type MCF-7 and MDA-MB-231 breast cancer cell lines as well as cancer cells deprived of mitochondrial DNA (ρ0 cells) were employed in order to assess thioalbamide effects on tumor bioenergetics. In this regard, metabolic profile was evaluated by a Seahorse XFe96 analyzer, and the activity of the enzyme complexes involved in oxidative phosphorylation was quantified by spectrophotometric assays. Thioalbamide effects on tumor invasiveness were assessed by gelatin zymography experiments and invasion assays. In vivo experiments were carried out on breast cancer xenograft and "experimental metastasis" mouse models. RESULTS: Experiments carried out on ρ0 breast cancer cells, together with Seahorse analysis and the application of spectrophotometric enzymatic assays, highlighted the ability of thioalbamide to affect the mitochondrial respiration process, and allowed to propose the FoF1-ATPase complex as its main molecular target in breast cancer cells. Additionally, thioalbamide-mediated OXPHOS inhibition was shown, for the first time, to reduce tumor invasiveness by inhibiting metalloproteinase-9 secretion. Furthermore, this study has confirmed the antitumor potential of thioalbamide in two different in vivo models. In particular, experiments on MCF-7 and MDA-MB-231 xenograft mouse models have confirmed in vivo its high anti-proliferative and pro-apoptotic activity, while experiments on MDA-MB-231 ″experimental metastasis" mouse models have highlighted its ability to inhibit breast cancer cell invasiveness. CONCLUSIONS: Overall, our results shed more light on the molecular mechanisms underlying the pharmacological potential of thioamidated peptides, thus reducing the gap that separates this rare class of microbial metabolites from clinical studies, which could validate them as effective tools for cancer treatment.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , ATPasas de Translocación de Protón , Animales , Femenino , Humanos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , Invasividad Neoplásica , Péptidos/farmacología , ATPasas de Translocación de Protón/antagonistas & inhibidores
5.
Mini Rev Med Chem ; 16(8): 619-29, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26156545

RESUMEN

Elevated serum cholesterol, triglycerides and LDL levels are often associated with an increased incidence of atherosclerosis and coronary artery disease. The most effective therapeutic strategy against these diseases is based on statins administration, nevertheless some patients, especially those with metabolic syndrome fail to achieve their recommended LDL targets with statin therapy, moreover, it may induce many serious side effects. Several scientific studies have highlighted a strong correlation between diets rich in flavonoids and cardiovascular risk reduction. In particular, Citrus bergamia Risso, also known as bergamot, has shown a significant degree of hypocholesterolemic and antioxidant/radical scavenging activities. In addition, this fruit has attracted considerable attention due to its peculiar flavonoid composition, since it contains some flavanones that can act as natural statins. Hence, the study of bergamot flavonoids as metabolic regulators offers a great opportunity for screening and discovery of new therapeutic agents. Cholesterol metabolism, flavonoid composition and potential therapeutic use of C. bergamia Risso will be discussed in the following review.


Asunto(s)
Aterosclerosis/tratamiento farmacológico , Citrus/química , Flavonoides/uso terapéutico , Hiperlipidemias/tratamiento farmacológico , Animales , Flavonoides/química , Flavonoides/aislamiento & purificación , Humanos , Estructura Molecular
6.
Anal Bioanal Chem ; 398(5): 2163-71, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20835864

RESUMEN

An automated in-capillary assay requiring very small quantities of reagents was developed for performing in vitro cytochrome P450 (CYP450) drug metabolism studies. The approach is based on the following: (i) hydrodynamic introduction of nanoliter volumes of substrate and enzyme solutions in the sandwich mode, within a capillary; (ii) mixing the reagents by diffusion across the interfaces between the injected solutions; (iii) collection of the capillary content at the end of the in-capillary assay; and (iv) off-line analysis of the incubation mixture by ultrahigh pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). After optimizing the injection sequence of the reagents, the in-capillary approach was applied to the quantitative determination of the kinetics of drug metabolism reactions catalyzed by three CYP450 isozymes involved in human drug metabolism: CYP1A2, CYP2D6, and CYP3A4. It was demonstrated that this in-capillary method was able to provide similar kinetic parameters for CYP450 activity (e.g., Michaelis constants and turnover values) as the classical in vitro method, with a drastic reduction of reagent consumption.


Asunto(s)
Bioensayo/métodos , Sistema Enzimático del Citocromo P-450/análisis , Cromatografía Liquida/métodos , Sistema Enzimático del Citocromo P-450/metabolismo , Humanos , Cinética , Espectrometría de Masas
7.
J Mol Biol ; 357(4): 1306-21, 2006 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-16483608

RESUMEN

A novel computational approach to the structural analysis of ordered beta-aggregation is presented and validated on three known amyloidogenic polypeptides. The strategy is based on the decomposition of the sequence into overlapping stretches and equilibrium implicit solvent molecular dynamics (MD) simulations of an oligomeric system for each stretch. The structural stability of the in-register parallel aggregates sampled in the implicit solvent runs is further evaluated using explicit water simulations for a subset of the stretches. The beta-aggregation propensity along the sequence of the Alzheimer's amyloid-beta peptide (Abeta(42)) is found to be highly heterogeneous with a maximum in the segment V(12)HHQKLVFFAE(22) and minima at S(8)G(9), G(25)S(26), G(29)A(30), and G(38)V(39), which are turn-like segments. The simulation results suggest that these sites may play a crucial role in determining the aggregation tendency and the fibrillar structure of Abeta(42). Similar findings are obtained for the human amylin, a 37-residue peptide that displays a maximal beta-aggregation propensity at Q(10)RLANFLVHSSNN(22) and two turn-like sites at G(24)A(25) and G(33)S(34). In the third application, the MD approach is used to identify beta-aggregation "hot-spots" within the N-terminal domain of the yeast prion Ure2p (Ure2p(1-94)) and to design a double-point mutant (Ure2p-N4748S(1-94)) with lower beta-aggregation propensity. The change in the aggregation propensity of Ure2p-N4748S(1-94) is verified in vitro using the thioflavin T binding assay.


Asunto(s)
Péptidos beta-Amiloides/química , Amiloide/química , Simulación por Computador , Fragmentos de Péptidos/química , Priones/química , Estructura Secundaria de Proteína , Proteínas de Saccharomyces cerevisiae/química , Secuencia de Aminoácidos , Amiloide/genética , Amiloide/metabolismo , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glutatión Peroxidasa , Humanos , Polipéptido Amiloide de los Islotes Pancreáticos , Modelos Moleculares , Conformación Molecular , Datos de Secuencia Molecular , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Mutación Puntual , Priones/genética , Priones/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Alineación de Secuencia
8.
Rev. bras. implantodontia ; 9(1): 5-6, jan.-mar. 2003. ilus
Artículo en Portugués | BBO - Odontología | ID: biblio-857323

RESUMEN

Pacientes com câncer avançado de cavidade oral estádios III e IV evoluem com prognóstico sombrio, porém não são excluídos de necessidade de reabilitação. Relatamos o caso de paciente que apresentou tumor primário de língua extenso tratado com glossectomia total e radioterapia pós-operatória e que, quatro anos após tratamento, desenvolveu uma segunda lesão em palato duro, tratado com radioterapia e resgate cirúrgico com ressecção total da infraestrutura do maxilar. Apesar do prognóstico reservado, o paciente foi reabilitado com implantes osseointegrados e prótese com sucesso, mesmo após a radioterapia


Asunto(s)
Neoplasias de la Boca , Oseointegración , Hueso Paladar , Neoplasias de la Lengua
9.
Healthc Financ Manage ; 42(9): 62-4, 66, 68 passim, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10312677

RESUMEN

Nursing care is a very significant part of a healthcare organization's costs. However, until recently, methods of controlling nursing costs were largely ineffective. With the implementation of the prospective payment system and the use of diagnosis related groups, budgeting and controlling nursing costs are now possible with the use of standard costing. In this article, methods and procedures are discussed and explained for controlling inpatient nursing costs with the use of DRGs and standard costs.


Asunto(s)
Contabilidad/métodos , Grupos Diagnósticos Relacionados/economía , Servicio de Enfermería en Hospital/economía , Administración de Personal/economía , Admisión y Programación de Personal/economía , Análisis de Varianza , Presupuestos , Control de Costos/métodos , Costos y Análisis de Costo , Tiempo de Internación/economía , Estados Unidos
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